Intro to Information Systems I

1
Intro to Information Systems I

• Multimedia and Communications
• ISYS 101
• Glenn Booker

2
Multimedia World

• Multimedia presentations go beyond the vu-graph
  mode of presentation applications to blend
  graphics, animation, video, and sound
• Metaphor becomes theater instead of a podium
  presentation
• Many multimedia tools are designed for the Web

3
Interactivity

• A major feature of multimedia presentations can
  be the use of interactive elements where the
  viewer chooses their path through the
  presentation instead of seeing a fixed series of
  events
• Normal web pages achieve interactivity through
  hyperlinks

4
Multimedia Hardware

• Basic input and output hardware for multimedia
  include a CD-ROM or DVD-ROM drive, sound card,
  and speakers (all now standard on personal
  computers)
• Optional equipment includes a microphone,
  graphics tablet, digital camera, and a TV video
  adapter

5
Multimedia Hardware

• Faster video cards and 3-5 speakers instead of
  just one or two (e.g. adding a subwoofer or going
  for surround sound or theater-grade THX sound)
  help too

6
Multimedia Uses

• Multimedia is used increasingly for
• Computer based training (CBT) or education (CBE)
• Livening up reference materials (encyclopedias)
• Creating stand-alone sales or information kiosks,
  playing a loop of information
• Even art is starting to use multimedia

7
Big Files Need Compression

• Multimedia takes a lot more disk space than text,
  so compression techniques are important
• Algorithms are used to calculate how data can be
  compressed these algorithms are called codecs
  (for compression/ decompression)

8
Compression Types

• Compression techniques can be lossless or lossy
• Lossless techniques retain every bit of original
  data (literally!)
• Lossy techniques sacrifice some low level data
  detail to produce higher levels of compression

9
Graphics Compression Formats

• GIF (like gift without the t) allows a
  maximum of 256 colors (8-bit), uses lossless
  compression, and is often used for simpler Web
  graphics
• JPEG allows up to 16.7 million colors (24-bit),
  is lossy, and often used for photos or other
  complex images on the Web

10
Graphics Compression Formats

• PNG is a new format like GIF, but isnt
  proprietary (you have to pay royalties to be able
  to create GIF images)
• Bitmap (BMP) is the Windows standard for
  primitive graphics is often without
  compression, so bitmaps are huge
• A bitmap describes every pixels color

11
Graphics Software

• Graphics software programs tend to fall into
  three types for working with a single image
• Paint programs, which use bit-mapped or raster
  graphics
• Drawing programs, which use vector graphics
• Image editors, for modifying existing photos

12
Paint Programs

• Paint programs are designed to create images at
  the pixel level
• Easy to create stuff this way, but harder to
  edit, and harder to keep smooth
• Examples Fractal Design Painter, Paint Shop Pro,
  Corel Painter

13
Drawing Programs

• Drawing programs use vector graphics each line
  is described by a math formula
• Draw and shape lines, then fill in colors and
  textures among them
• Creates smoother images, which can be scaled to
  any size

14
Drawing Programs

• Saves documents in EPS format, which some
  printers understand
• But EPS isnt Web friendly
• Examples Adobe Illustrator, Macromedia
  Freehand, CorelDRAW

15
Image Editors

• Image editors are for manipulating existing
  pictures (e.g. photos)
• Allow you to resize, crop, merge and add special
  effects to the images
• Examples Adobe Photoshop and PhotoDeluxe

16
Moving Picture Software

• Programs for working with moving pictures
  include
• 3-D rendering programs, for adding 3-D effects to
  graphics (lighting, shadows, etc.)
• Animation programs, for creating the illusion of
  moving pictures through graphics
• Video editors, for creating and editing digital
  videos

17
3-D Rendering Programs

• Rendering programs account for specific light
  sources, and determine shadows, transparency, and
  other effects
• Used to require a supercomputer to do this
• Ray tracing is one technique they use
• Examples Renderman, AutoCAD, 3D Studio MAX

18
Animation Programs

• Animation is based on presenting still images
  rapidly in succession
• A movie uses 24 frames per second
• Computer animation uses the same idea with GIF
  images
• Some programs recognize background images versus
  those elements which move

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Animation Programs

• Examples Adobe LiveMotion, Macromedia Flash, and
  Softimage XSI
• Some high end () programs combine animation
  with 3D rendering, such as Discreet combustion,
  Maya Complete, and Newtek Lightwave

20
Video Editors

• Video editors take input from a digital video
  camera, and allow it to be rearranged, add sound,
  etc.
• Examples Adobe Premiere

21
Video Formats

• Videos are usually in one of three formats
• MPEG is the standard for full motion video, such
  as DVDs
• QuickTime is an Apple standard for high quality
  video and audio
• AVI (formally Video for Windows) tend to be
  fairly low quality

22
Streaming Video

• One way to get video across the Internet quickly
  is to use streaming video
• A small bit of video is sent continuously to the
  viewer
• Hence the viewer doesnt need to download the
  entire video before watching it
• But the viewer also never has a copy of the video
  either

23
Audio Software

• Audio software has improved to where most
  professional recording studios dont bother with
  magnetic tape for recording they use computers
  instead
• Sound uses can range from simple background music
  to original compositions

24
Audio Formats

• Audio is digitized at 44.1 kHz for CDs
• Raw audio files are very large, hence compression
  is important
• MP3 is the most common format, can be compressed
  up to 1/12th of original size
• AU format is used on Sun workstations
• WAV files are used in Windows, arent compressed

25
Audio Software

• Musical instruments use MIDI language to speak to
  computers
• Audio applications include
• Notation programs to write music
• Recording and editing programs
• Mixers and synchronizers to coordinate many
  musical parts into one piece

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Putting it all together

• Authoring software is used for assembling
  multimedia presentations from all of its parts
  (sound, graphics, video, animation)
• Uses a scripting language to coordinate
  activities
• Example Macromedia Director

27
Virtual Environments

• Massive improvements in multimedia have led to
  the concept of creating virtual environments
• Hardware like head-mounted displays make it
  possible to present a realistic fake environment

28
Virtual Formats

• VRML (Virtual Reality Modeling Language) is a
  front-runner in providing a virtual environment
  via the Internet
• Used for games, training, and data visualization
• One common game environment is the Multi-User
  Dungeon (MUD)

29
Telecommunications

• Some aspects of computer networking depend on the
  existing telecommunications infrastructure
• Most home users use analog telephone lines for
  their modem connection to the Internet
• Telecom is moving from analog signals on copper
  wires to digital signals

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Telecommunications

• Analog wires can go up to T1 speed (1.5 Mb/s) or
  24 voice signals
• Digital signals may be sent across fiber optic
  cables, or beamed using microwaves
• Fiber optics can go up to T3 speed (43 Mb/s) or
  672 voice signals using pulses of light

31
Telecom Standards

• Telecom standards are defined by the ITU, a
  branch of the United Nations
• Telecom is a vital service for safety, so it is
  heavily regulated to ensure service to
  unprofitable regions
• Private or leased lines can be used for
  communication too

32
Modems

• Modems modulate and demodulate signals
• That converts a digital signal to analog, and
  back again at the other end
• Modem speeds evolved from 300 bits/sec (circa
  1970s) to the theoretical limit of 56,000 bps

33
Modem Standards

• The current limit is defined by the V.90 standard
  (56 kbps)
• Earlier standards were V.34 (28.8 kbps) and V.32
  (14.4 kbps)
• Modems negotiate the fastest connection both
  sides can handle
• Faxes can also be sent, generally at 9.6 kbps

34
Need for Speed

• Bandwidth, or the speed at which data can be sent
  and received, is critical for emerging
  applications
• Video conferencing needs 10 Mbps
• High definition TV (HDTV) needs 11 Mbps
• Broadband refers to digital telecom at speeds of
  1.5 Mbps and up (T1 or better)

35
Broadband Options

• ISDN is the most common broadband service
• Basic ISDN goes up to 128 kbps
• Primary ISDN goes up to 1.5 Mbps (T1)
• Broadband ISDN doesnt exist yet claims up to
  622 Mbps

36
Broadband Options

• Digital Subscriber Lines (DSL) is still rare
• Some versions are asymmetric (you can have much
  slower upload speed than download)
• Range from 128 kbps to 9.1 Mbps speeds
• Speed varies depending on how far you are from
  the provider
• SONET is a future possibility range from 52 Mbps
  to 1 Gbps

37
Cable Modems

• Cable modems use coaxial cable from your TV cable
  provider to feed Internet access
• Cable bandwidth is shared among the users in the
  local area more users online means slower
  speeds for each user
• Speed can range from 100 kbps to over 2000 kbps

38
Power Lines?

• Internet connections can be passed over power
  lines too
• Still experimental
• Not likely to work in the US

39
Phone, TV, and Internet Merge

• Some appliances can let a normal TV show the
  Internet (WebTV)
• Phone service and Internet service can share the
  same lines, and some computer applications handle
  phone and fax functions over normal phone lines
• The lines of distinction are blurring

40
Computer Networking

• Networking allows computers to communicate with
  each other, and share resources (e.g. printers)
• Networks range in size from global to consumer
• Networks are much faster than just using telecom
  equipment

41
Types of Networks

• A single building or group of buildings might use
  a Local Area Network (LAN)
• Several related sets of facilities might use a
  Metropolitan Area Network (MAN)
• Global corporations use a Wide Area Network (WAN)
• Networks can be public or private

42
Switching

• Networks control the flow of data using switching
• Two major types of switching
• Circuit switching changes the circuit to produce
  a physically direct connection is very fast
• Packet switching sends packets of data which get
  reassembled at the other end to produce the
  message is much cheaper than circuit

43
Protocols

• Network protocols are the language spoken across
  the network
• TCP/IP is the language of the Internet
• NetBEUI is a Windows networking protocol
• AppleTalk is an Apple networking protocol
• IPX is a Novell protocol

44
Network Layers

• Networks function by taking data and adding
  various pieces of information to it in order to
  help it get to its destination
• The layers of the network describe what that
  information is and how it is used
• The OSI reference model is the most common system
  for networking

45
Network Hardware

• Networks rely on each computer having a network
  interface card (NIC) to allow them to be
  connected to the network
• Like a modem allows connection to the Internet
• Most NICs are for Ethernet networks
• Ethernet speeds include 10, 100, and 1000 Mbps
  (the last one is Gigabit Ethernet)

46
Network Hardware

• Most networks still use cables
• Thick, thin, or 10base-T Ethernet cables
• Token Ring cables
• Coaxial cable
• Fiber-optic cable
• Infrared and radio signals are used for wireless
  networks

47
Network Hardware

• Other network hardware might include
• Switches, to control where data may go
• Router, to convert one language into another
• Hubs, to connect computers which speak the same
  language (protocol)
• Bridges, to connect major parts of the network
  together

48
Network Terminology

• Every device on a network (computer, printer,
  etc.) is a node
• Peer to peer networks work well for small offices
  and home allow sharing of files, printers, and
  Internet connection
• Client/server networks use servers to manage the
  network, and control access to different nodes

49
Network Operating System

• Normal operating systems routinely include
  software to allow peer to peer networking
• Client/Server networks require a networking
  operating system (NOS)
• Windows Servers (NT, 2000, etc.)
• Novell NetWare
• Unix

50
Network Topology

• Network topology is the layout of a network, like
  a street map to show where roads go
• The bus topology connects everything along a
  line (like a bus route) good for peer to peer
  networks

51
Network Topology

• A star topology puts a hub in the middle, and
  everything connects to it
• A ring topology passes information in a circle,
  and every computer either passes it along or uses
  it (e.g. IBMs Token Ring)
• More complex topologies are variants on these
  basic structures

52
WAN Structure

• WANs are essentially a group of networks which
  are connected by a backbone (generally a very
  fast dedicated connection)
• Most use circuit switching, not packet
• Each local network connects to the WAN via a POP
  (point of presence), similar to how you connect
  to the Internet

53
WAN Protocols

• Special protocols are used for WANs
• X.25 is for phone line connections, goes up to 64
  kbps (like MAC machines)
• ATM (Asynchronous Transfer Mode) goes up to 155
  Mbps

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Why WAN?

• Most WANs are used for sharing files and email
  across a large organization
• Some also handle transactions (e.g. credit card
  authorization)
• Specific business-to-business transactions can be
  done securely using Electronic Data Interchange
  (EDI) standards